A high-speed missile optical transmission effect test device and method

Abstract

The application discloses a high-speed missile optical transmission effect test device and method, and belongs to the field of missile test technology.The mixed stable pressure chamber of the device is located between an arc heater and a nozzle, a window assembly is fixedly installed on a test station through a support, and a seeker is installed in the window assembly.The seeker is connected with a signal acquisition computer through an optical cable.An L-shaped guiding device is integrally designed at the outlet of the nozzle, a shielding protection device is installed on the L-shaped guiding device, a driving shaft of a feeding mechanism is connected with the shielding protection device, and a simulated target is located on the extension line of the connecting line between the seeker and the fixed wall of the nozzle.The application solves technical problems such as optical transmission fixed wall interference and optical window cold and hot alternating protection.

Description

TECHNICAL FIELD

[0001] The application provides a high-speed missile optical transmission effect test device and method, which is used for examining the imaging effect of an optical guidance system of a high-speed air-to-air missile, an air-to-ground missile or the like on a simulated target under an electric arc heating ground simulation test condition, and belongs to the field of ground simulation test devices of aircrafts. BACKGROUND

[0002] High-speed air-to-air missiles, air-to-ground missiles and the like aircrafts using infrared terminal guidance technology fly at a speed of 2-3 Mach in a dense atmosphere after being released at a certain height in the terminal trajectory, the optical window at the head is usually made of infrared glass materials such as zinc sulfide, magnesium fluoride, spinel and sapphire, and is the most seriously aerodynamic heating load part, the higher window temperature and temperature gradient will interfere with the transmission of the optical imaging detection system, causing target image shift, jitter, blur and other distortions, which seriously affect target recognition, and this phenomenon is called aerodynamic optical effect. At present, more and more weapons use infrared terminal guidance technology, and in the development process, aerodynamic optical effect ground simulation test research is needed to test whether the window can withstand the thermal shock of the thermal performance and the optical transmission performance indicators of the seeker system, and to approximately obtain the target recognition effect under the real flight condition, so as to provide technical support for the heat protection design of the window assembly and the optical design and algorithm improvement of the seeker system.

[0003] The electric arc heating ground test equipment has the advantages of real gas composition, wide parameter adjustment range and long time heating, and becomes the first choice for aerodynamic heating simulation test, but it is generally used for conventional material screening and ablation performance research according to the needs of weapon types. However, the current electric arc heating ground test has the following problems:

[0004] When the optical imaging effect test is carried out, the detector located in the spherical cap glass window needs to observe the simulated target against the airflow, and the solid wall interference with the test equipment such as the nozzle will occur, that is, the problem of observing the stagnation point for a long time has plagued the test field;

[0005] The optical window is generally made of various optical glasses, which has thermal brittleness, and before / after the electric arc heater is formally worked, an equal amount of cold air will inevitably flow out from the heater, and if it is directly blown to the window surface, it will bring the risk of abnormal fragmentation caused by rapid heating / cooling effect to the window.

[0006] Therefore, in view of the current window system comprehensive test requirements put forward by the type department, the joint test technology of heat-force-light is needed to be developed based on the electric arc heating ground simulation test equipment, and a reasonable test device is needed to be designed to solve the technical problems of solid wall interference of stagnation point against airflow observation and easy fragmentation of crystal materials caused by rapid cooling and heating. SUMMARY

[0007] The technical solution of the present application is to overcome the shortcomings of the prior art, provide a high-speed missile optical transmission effect test device and method, and solve the technical problems of observing the fixed wall interference and the crystal material being easily broken by rapid cooling and heating.

[0008] The technical solution of the present application is:

[0009] The high-speed missile optical transmission effect test device comprises an arc heater, a mixed pressure stabilizing chamber, a nozzle, a shielding protection device, a window assembly, a seeker, an optical cable, a signal acquisition computer, a support, a simulated target and a feeding mechanism.

[0010] The mixed pressure stabilizing chamber is located between the arc heater and the nozzle, the window assembly is fixedly installed at a test station through the support, the test station is located in front of the nozzle outlet, and the seeker is installed in the window assembly; the seeker is connected with the signal acquisition computer through the optical cable.

[0011] An L-shaped guiding device is integrally designed at the nozzle outlet, the shielding protection device is installed on the L-shaped guiding device, and a driving shaft of the feeding mechanism is connected with the shielding protection device.

[0012] The simulated target is located on an extension line of a connecting line between the seeker and the fixed wall of the nozzle.

[0013] Preferably, the Mach number of the nozzle is 2.

[0014] Preferably, a spherical cap type optical glass window is embedded in the head of the window assembly, and the outlet diameter of the nozzle is the same as the glass window diameter of the head of the window assembly.

[0015] Preferably, the seeker is installed in the window assembly and closely abuts against the glass window of the head of the window assembly.

[0016] Preferably, the field of view angle of the seeker is adjustable.

[0017] Preferably, the seeker is located on the device axis and is deflected by a certain angle relative to the window assembly, so that the optical observation line of sight of the seeker to the simulated target can avoid the interference of the fixed wall of the nozzle.

[0018] Preferably, the horizontal axes of the arc heater, the mixed pressure stabilizing chamber and the nozzle are collinear, that is, the device axis.

[0019] Preferably, the position of the simulated target should meet the following condition: under the premise that the connecting line between the simulated target and the seeker can avoid the fixed wall of the nozzle, the deflection angle of the window assembly relative to the device axis is the smallest.

[0020] The high-speed missile optical transmission effect test method comprises the following steps:

[0021] Placing the simulation target in a proper position;

[0022] Determining the axial position of the window assembly to prevent it from being broken during the operation of the protection device;

[0023] Powering on and adjusting the field of view angle of the seeker to the maximum to minimize the deflection angle of the window assembly;

[0024] Rotating the window assembly to an initial angle under the condition that the seeker is kept on the axis of the device so that the line of sight of the seeker can observe the simulation target, then gradually reducing the rotation angle of the window assembly and synchronously tracking and adjusting the position of the simulation target until it just avoids the wall of the nozzle, and then fixing the window assembly and the simulation target respectively;

[0025] Starting the signal acquisition computer to begin pre-acquisition of the initial image of the simulation target collected by the seeker;

[0026] Feeding the protection device into the space between the nozzle and the window assembly through the feeding mechanism;

[0027] Synchronously supplying a certain proportion of normal-temperature gas to the arc heater and the mixing plenum until the flow reaches stability, at which time the cold gas flows away from the front of the protection device;

[0028] Starting the arc heater to heat air, and the hot gas flow is fully mixed with the normal-temperature gas injected quantitatively in the mixing plenum and is stabilized, and then is ejected from the nozzle;

[0029] After the arc heater is started, the protection device is pulled out of the flow field by the automatic feeding mechanism, at which time the hot gas flow forms a detached shock wave in front of the window assembly, and the hot gas flow that has passed through the shock wave continues to load the window assembly with heat and force;

[0030] During the test, the optical signal from the simulation target passes through the low-density flow field in front of the shock wave, the shock wave, the high-density flow field behind the shock wave, and the hot window assembly into the field of view of the seeker, and the temperature and density in the optical path change dramatically, which will cause optical distortion. The distorted image signal is collected and processed by the seeker, and then is transmitted to the signal acquisition computer by the optical cable for recording and saving;

[0031] After the predetermined test time is reached, the protection device is fed into the flow field by the feeding mechanism, the arc heater is turned off, and the hot gas flow is converted into cold gas flow immediately after the parking to continue to be ejected from the nozzle and to flow away from the front of the protection device, thereby preventing the abnormal fragmentation of the window caused by rapid cooling;

[0032] After the working medium of the arc heater is completely cut off, the protection device is again withdrawn from the flow field by the feeding mechanism, and the signal acquisition computer continues to collect the image signal of the simulation target collected by the seeker;

[0033] Stop signal acquisition, the result is analyzed and processed, if the result is not ideal, improve the device parameters and then carry out the next test, until the test process can obtain satisfactory simulation target image signal;According to the simulation target image signal obtains the optical transmission effect of missile.

[0034] Preferably, when determining the axial position of the window assembly, the horizontal distance between the front end of the window assembly and the shielding protection device should be 5mm.

[0035] The beneficial effects of the present application are as follows:

[0036] The present application closely combines the special requirements of the heat, force and light combined test of the optical transmission effect test of the terminal guidance optical window, relies on the electric arc heating ground test equipment, innovatively develops a new type of test device, solves the technical problems of observing the counter airflow at the stagnation point and the window quick cooling / heat easy to crack, etc., so that the aerodynamic heating test and optical effect research can be organically combined together in the ground test, has strong comprehensive utilization value, has successfully provided services for multiple air-to-ground missiles, air-to-air missiles and other models, and provided test data for the ground reproduction of flight failure of some models, solved the optimization verification of the improved optical detection system of multiple models, and filled the domestic blank. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 It is a schematic diagram of the test device;

[0038] Figure 2 It is an optical window in the test process;

[0039] Figure 3 It is the simulation target image obtained in the test process. DETAILED DESCRIPTION

[0040] The present application is composed of an electric arc heater 1, a mixed pressure stabilizing chamber 2, a nozzle 3, a shielding protection device 4, a window assembly 6, a seeker 7, an optical cable 8, a signal acquisition computer 9, a support 10, a simulation target 11 and a feeding mechanism 12, and the connection order is as shown in Figure 1 .

[0041] The mixing plenum 2 is located between the arc heater 1 and the nozzle 3, the window assembly 6 is fixedly installed on the test station through the support 10, the test station is located in front of the nozzle 3 outlet, the seeker 7 is installed in the window assembly 6, and the seeker 7 is connected with the signal acquisition computer 9 through the optical cable 8. The "L" type guide device is integrally designed at the nozzle 3 outlet, the shielding protection device 4 is installed on the "L" type guide device, and the driving shaft of the feeding mechanism 12 is connected with the shielding protection device 4. The "L" type guide device integrally designed on the nozzle 3 limits the shielding protection device 4 and enables the shielding protection device 4 to smoothly slide on the extension line of the seeker 7 and the fixed wall of the nozzle 3. The optimal Mach number of the nozzle 3 is 2, the outlet diameter of the nozzle 3 is designed according to the diameter of the glass window of the head of the window assembly 6, and the design criterion is that the sizes are equivalent. The shielding protection device 4 is designed between the nozzle 3 and the window assembly 6, and the shielding protection device 4 is controlled by the feeding mechanism 12 and can realize automatic feeding and exiting. The window assembly 6 is embedded with a spherical cap optical glass window, and the material, size, connection and sealing form of the window are determined according to the design requirements of the type. The seeker 7 is installed in the window assembly 6 and closely contacts the glass window to realize wider angle observation, and the field of view angle can be adjusted. Under the condition that the seeker 7 is located on the device axis, the window assembly 6 is deflected by a certain angle, so that the optical observation line of the simulated target 11 can avoid the interference of the fixed wall of the nozzle 3. The simulated target 11 is located on the extension line of the seeker 7 and the fixed wall of the nozzle, and the front and back distance is determined according to the optical image of the simulated target 11 received by the seeker 7. The optical signal emitted by the simulated target 11 passes through the shock wave 5 to the seeker 7, and the obtained optical signal is transmitted to the signal acquisition computer 9 through the optical cable 8.

[0042] The air is heated by the arc heater 1 to become a high-temperature airflow.

[0043] A certain amount of normal-temperature airflow and high-temperature airflow are mixed and cooled in the mixing plenum 2 to achieve the required simulated incoming flow temperature.

[0044] The incoming flow is made into supersonic airflow by the nozzle 3, and a detached shock wave 5 is formed in front of the window assembly 6, and the hot airflow after passing through the shock wave 5 continuously aerodynamically heats the window assembly 6.

[0045] The optical signal from the simulated target 11 passes through the pre-shock flow field, the shock wave, the post-shock flow field and the high-temperature window to reach the seeker 7, the seeker 7 modulates the obtained optical signal and transmits the optical signal to the signal acquisition computer 9 through the optical cable 8 for recording and saving.

[0046] The shielding protection device 4 is controlled by the feeding mechanism 12 and is in the feeding state before the arc is started and after the arc is broken to isolate the cold airflow and ensure that the hot airflow blows on the window assembly 6 from the beginning to the end.

[0047] This invention heats air to several thousand Kelvin using an electric arc heater 1. A certain amount of cold air is injected into the mixing and stabilizing chamber 2 and mixed with the upstream hot airflow to achieve the required simulated airflow temperature. The mixed airflow expands and accelerates through the nozzle 3, forming a detached shock wave 5 in front of the window assembly. The position of the simulated target 11 is determined in advance by the standard that the window assembly 6 has the smallest deflection angle relative to the device axis, provided that the line connecting the simulated target 11 and the seeker head 7 can avoid the solid wall of the nozzle. During the experiment, the optical signal from the simulated target 11 passes sequentially through the low-density flow field before the shock wave, the shock wave 5, the high-density flow field after the shock wave, and the hot window to reach the seeker head 7. The seeker head 7 modulates the acquired optical signal and transmits it to the signal acquisition computer 9 via the optical cable 8 for recording and storage.

[0048] Before the arc heater 1 is ignited and before the arc is broken, the feeding mechanism 12 controls the shielding protection device 4 to keep it in the feeding state. After the arc heater 1 is started and the flow field is stable, the feeding mechanism 12 controls the shielding protection device 4 to exit the flow field, fully exposing the window assembly 6 so that it can be subjected to pneumatic heating.

[0049] The optical effect transmission experiment using this experimental system includes the following steps:

[0050] (a) Place the simulated target 11 in a suitable position;

[0051] (b) Determine the axial position of the window assembly 6 so that its foremost point is approximately 5 mm from the obstruction and protection device 4.

[0052] The protective device 4 prevents the window assembly 6 from breaking during operation;

[0053] (c) Power on the entire optical system and adjust the field of view of the guide head 7 to the maximum so that the deflection angle of the window assembly 6 is minimized, so that the line of sight of the guide head 7 can pass through the central area as much as possible, which is also conducive to the uniform heat distribution of the window.

[0054] (d) While keeping the seeker head 7 on the system axis, rotate the window assembly 6 to an initial angle so that the seeker head 7 can observe the simulated target 11. Then gradually reduce the rotation angle of the window assembly 6 and synchronously track and adjust the position of the simulated target 11 until it can just avoid the nozzle solid wall. Then fix the window assembly 6 and the simulated target 11 respectively.

[0055] (e) Start the signal acquisition computer 9 and begin pre-acquiring the initial image of the simulated target 11;

[0056] (f) The shielding protection device 4 is fed into the space between the nozzle 3 and the window assembly 6 by the feeding mechanism 12;

[0057] (g) The electric arc heater 1 and the mixing plenum 2 are supplied with a certain proportion of cold air simultaneously until the flow reaches stability, at which time the cold air flows away from the front of the shield 4;

[0058] (h) The electric arc heater 1 is started to heat air, and the hot air is mixed with the cold air injected in a certain amount in the mixing plenum 2 and is discharged from the nozzle 3 after being stabilized;

[0059] (i) After the electric arc heater 1 is started, the shield 4 is pulled out of the flow field by the automatic feed mechanism 12, at which time the hot air forms a detached shock wave 5 in front of the window assembly 6, and the hot air passing through the shock wave 5 continues to load the window assembly 6 with heat and force. As the test proceeds, the temperature of the window rises continuously and produces a temperature difference between the inner and outer walls, which will affect the optical signal passing through, causing blurring or distortion;

[0060] (j) During the test, the optical signal from the simulated target 11 passes through the low-density flow field in front of the shock wave, the shock wave 5, the high-density flow field behind the shock wave, and the hot window, and enters the field of view of the seeker 7. The temperature and density in the optical path change dramatically, causing optical distortion. The distorted image signal is collected and processed by the seeker 7 and is transmitted to the signal acquisition computer 9 by the optical cable 8 for recording and preservation;

[0061] (k) After the predetermined test time is reached, the shield 4 is fed into the flow field by the feed mechanism 12, the electric arc heater 1 is turned off, and the hot air is converted to cold air immediately after the test is stopped and continues to be discharged from the nozzle 3 and flows away from the front of the shield 4, eliminating the phenomenon of abnormal window fragmentation caused by rapid cooling.

[0062] (l) After the working medium of the electric arc heater 1 is completely cut off, the shield 4 can be withdrawn from the flow field again by the feed mechanism 12 to obtain the influence of the static high-temperature window on the optical signal;

[0063] (m) The signal acquisition is stopped, and the acquisition results are analyzed and processed. If the test results are not satisfactory, the optical system parameter settings are improved, and the next test is performed until satisfactory simulated target image signals are obtained during the test process. Thus, the optical effects of the missile are obtained.

[0064] Using this set of test devices, optical transmission effect simulation tests of multiple optical terminal guidance, especially infrared guidance, have been successfully performed, Figure 2 the window (the interior is the seeker) during the test process, Figure 3 two simulated target infrared images obtained during the test process.

[0065] The application is used for ground examination and verification test research of imaging effect of analog target of optical guidance system of high-speed air-to-air missile, air-to-ground missile and other aircraft, relies on arc heating test equipment, closely combines special requirements of optical transmission heat-power-light combined loading test, innovatively designs test device and method, and solves technical problems such as optical transmission solid wall interference and optical window cold-hot alternating protection.

[0066] The undisclosed technology of the application is common knowledge of those skilled in the art.

Claims

1. A high-speed missile optical transmission effect test device, characterized in that: The device comprises an arc heater (1), a mixing steady chamber (2), a nozzle (3), a shielding protection device (4), a window assembly (6), a seeker (7), an optical cable (8), a signal acquisition computer (9), a support (10), a simulated target (11), a feeding mechanism (12); The mixing steady chamber (2) is located between the arc heater (1) and the nozzle (3), the window assembly (6) is fixed on the test station by the support (10), the test station is located in front of the nozzle (3) outlet, and the seeker (7) is installed in the window assembly (6); the seeker (7) is connected with the signal acquisition computer (9) through the optical cable (8); The "L" type guiding device is integrally designed at the nozzle (3) outlet, the shielding protection device (4) is installed on the "L" type guiding device, the driving shaft of the feeding mechanism (12) is connected with the shielding protection device (4), and the shielding protection device is fed to the nozzle (3) and the window assembly (6) through the feeding mechanism (12); The simulated target (11) is located on the extension line of the seeker (7) and the nozzle (3) fixed wall; The head of the window assembly (6) is inlaid with a spherical cap type optical glass window, and the outlet diameter of the nozzle (3) is the same as the glass window diameter of the head of the window assembly (6); The seeker (7) is located on the device axis and is deflected at a certain angle relative to the window assembly (6), so that the optical observation line of the seeker (7) to the simulated target (11) can avoid the interference of the nozzle (3) fixed wall.

2. The optical transmission effect test device for high-speed missile according to claim 1, characterized in that: The Mach number of the nozzle (3) is 2.

3. The optical transmission effect test device for high-speed missile according to claim 1, characterized in that: The seeker (7) is installed in the window assembly (6) and is close to the glass window of the head of the window assembly (6).

4. The optical transmission effects test device for high-speed missiles according to claim 3, characterized in that: The field of view angle of the seeker (7) is adjustable.

5. The optical transmission effects test apparatus for high-speed missiles according to claim 1, characterized in that: The horizontal axes of the arc heater (1), the mixing steady chamber (2) and the nozzle (3) are collinear, that is, the device axis.

6. The optical transmission effects test apparatus for a high-speed missile according to claim 5, characterized in that: The position of the simulated target (11) should meet the following conditions: under the premise that the line connecting the simulated target (11) and the seeker (7) can avoid the nozzle fixed wall, the deflection angle of the window assembly (6) relative to the device axis is the smallest.

7. A method for testing the optical transmission effects of a high-speed missile, characterized in that, The device comprises: Placing the simulated target (11) at a suitable position; Determining the axial position of the window assembly (6) to prevent the shielding protection device (4) from breaking the window assembly (6) during the action process; Powering on, adjusting the field of view angle of the seeker (7) to the maximum to make the deflection angle of the window assembly (6) the smallest; Under the condition that the seeker (7) is located on the device axis, rotating the window assembly (6) to a certain initial angle, so that the seeker (7) can observe the simulated target (11), then gradually reducing the rotation angle of the window assembly (6) and synchronously tracking and adjusting the position of the simulated target (11) until it can just avoid the nozzle fixed wall, then fixing the window assembly (6) and the simulated target (11) respectively; Starting the signal acquisition computer (9) to start pre-acquisition of the initial image of the simulated target (11) collected by the seeker; Feeding the shielding protection device (4) to the nozzle (3) and the window assembly (6) through the feeding mechanism (12); Synchronously supplying a certain proportion of normal temperature gas to the arc heater (1) and the mixing steady chamber (2) until the flow reaches stability, at this time, the cold gas flow is dispersed from the front of the shielding protection device (4); The arc heater (1) starts to heat air, the hot air flow mixes with the constant temperature air injected quantitatively in the mixing plenum (2) and is injected from the nozzle (3) after being stabilized; After the arc heater (1) starts, the shielding device (4) is pulled out of the flow field by the automatic feed mechanism (12), at this time the hot air flow forms a detached shock wave (5) in front of the window assembly (6), and the hot air flow passing through the shock wave (5) continues to load the window assembly (6) with heat and force; During the test, the optical signal from the simulated target (11) passes through the low-density flow field in front of the shock wave, the shock wave (5), the high-density flow field behind the shock wave, and the hot window assembly, and then enters the field of view of the seeker (7). The temperature and density in the optical path change sharply, causing optical distortion. The distorted image signal is collected and processed by the seeker (7), and then transmitted to the signal acquisition computer (9) by the optical cable (8) for recording and saving. After the predetermined test time is reached, the shielding device (4) is fed into the flow field by the feed mechanism (12), the arc heater (1) is turned off, and the hot air flow is converted to cold air flow immediately after the vehicle stops, which continues to be ejected from the nozzle (3) and dispersed from in front of the shielding device (4), eliminating the phenomenon of abnormal window fragmentation caused by rapid cooling. After the working medium of the arc heater (1) is completely cut off, the shielding device (4) is withdrawn from the flow field again by the feed mechanism (12), and the signal acquisition computer (9) continues to collect the image signal of the simulated target (11) collected by the seeker. Stop signal acquisition and analyze the collected results. If the results are not satisfactory, improve the device parameters and perform the next test until satisfactory simulated target image signals are obtained during the test process. According to the simulated target image signals, the optical transmission effect of the missile is obtained.

8. The method of claim 7, wherein the method further comprises: When determining the axial position of the window assembly (6), the horizontal distance between the front end of the window assembly (6) and the shielding device (4) should be 5mm.

Images